Long Range Acoustic Device
The Long Range Acoustic Device (LRAD) is an acoustic hailing device developed by LRAD Corporation to send messages and warning tones over longer distances or at higher volume than normal loudspeakers. LRAD systems are used for long range communications in a variety of applications including as a means of non-lethal, non-kinetic crowd control. Though they have been called "sonic weapons", LRADs are not inherently for military use.
According to the manufacturer's specifications, the systems weigh from 15 to 320 pounds (6.8 to 145.1 kg) and can emit sound in a 30°- 60° beam at 2.5 kHz. The manufacturer also produces systems for public address and mass notification use that broadcast 360°.
LRAD systems are used by maritime, law enforcement, military and commercial security companies to send instructions and warnings over distance, and can be used to initiate. LRAD systems are also used to deter wildlife from airport runways, wind and solar farms, nuclear power facilities, gas and oil platforms, mining and agricultural operations, and industrial plants.
The parameter "ka", which is the wave number multiplied by the speaker radius, is often used to characterize sound source directivity. For this source, ka=19 at 2.5 kHz, and according to the LRAD data sheet, the beam angle of about 30 degrees total is precisely what is predicted for a regular loudspeaker.
Small spherical "point-source" acoustic devices follow the known inverse square law, which predicts the loss of 6 decibels (dB) per doubling of distance from the source, solely due to geometric spreading. Large speakers (or large arrays), such as these, have an interference pattern in the nearfield which produces peaks 6 dB higher than the output pressure and nulls where the pressure is essentially zero. The larger the speaker, and the higher the frequency, the longer the effective nearfield. The nearfield for this device is approximately 8 metres (26 ft).
LRAD Corporation was formerly named American Technology Corporation.
Israel's Ministry of Defense ordered LRADs in June 2011.
LRAD was present, but not used, when the New York City Police department cleared Occupy Wall Street protestors from Zuccotti Park on the morning of 15 November 2011.
LRAD was present, but not used because of current legal regulations during protests in Poland, including Million Marijuana March 2011 and Marsz Niepodległości (National Independence Day March) 2011 and 2012. Lacking a way to utilize the LRADs purchased to their full potential sparked an investigation suspecting corruption behind their acquisition. National Police Headquarters spokesman Mariusz Sokolowski defended the purchase of LRAD. He also stressed that the police decided to make this investment because, "We needed good sound reinforcement equipment. With numerous demonstrations and gatherings, police need a public address system that allows you to reach thousands of people."
LRAD was deployed during a NATO march on May 20, 2012 in Chicago, Illinois at Michigan Ave. & Cermack.
The Salisbury, MD Police Department acquired an LRAD in October 2013 with proceeds from their speed cameras.
13, 18 August 2014 St. Louis County police used LRAD against protestors demonstrating the police shooting of Michael Brown in Ferguson, Missouri. Reporter Mike Tobin commented while broadcasting from Ferguson, MO on 18 August, “It doesn't have the effect of crippling people. It's just loud, it's annoying, it lets you know something big and official is coming and that’s what’s happening now. They can also use it as a loudspeaker to tell people to get out of the way.”
Myrtle Beach, South Carolina police obtained two LRAD systems through a federal grant in March 2015. Myrtle Beach police captain Marty Brown told the Myrtle Beach city council that 'his department is getting the LRADs to enhance their communication capabilities be it with large crowds or for emergency announcements such as evacuation orders.'
The NYPD used a Long Range Acoustic Device during the Baltimore solidarity rally in Union Square on April 29, 2015. An NYPD pickup truck equipped with an LRAD parked near protesters and began broadcasting a looped warning message about staying off the streets and not blocking the sidewalks.
The New Jersey State Police used an armored vehicle mounted LRAD on crowds denied entry to a June 7, 2015 concert after they began throwing bottles and tried to rush the gates outside MetLife Stadium.
The Greensboro, NC Police Department (GPD) purchased an LRAD 300X and demonstrated it for reporters in November 2015. Captain Jonathan Franks with GPD says it can be used for alerts for everything from riots to missing children to weather disasters. "I am sure, positive, 100% that in certain instances it will be able to not only save one life but numerous lives," said Franks.
Police in San Diego, CA used an LRAD on May 27, 2016 to order anti-Trump protesters to disperse.
LRAD emergency communication systems were demonstrated to city and county officials in Muskogee, Oklahoma in February 2015. "A warning system doesn't do much good if there's devastation and you can't communicate after that warning," said Muskogee Mayor Bob Coburn. "If your cell phone is down, your land line phone is down, [and] your power is out then you still have access to communicate and this [LRAD] has that potential."
For its multi-week March 2016 event, the Houston Livestock Show & Rodeo had an LRAD mass notification system on the grounds in case attendees needed to be warned of emergencies or extreme weather events.
The Singapore Navy is equipping its new fleet of eight littoral mission vessels with Long Range Acoustic Devices.
The Vietnam Coast Guard is deploying LRAD on its vessels.
RPB 33 coastal patrol boats in service with the navies of Senegal, Togo and Ivory Coast are equipped with LRADs for communication over long distances.
On November 5, 2005, the luxury cruise ship Seabourn Spirit employed an LRAD while repelling pirates who attacked the vessel with rocket-propelled grenades about 115 km off the coast of Somalia. The effectiveness of this device during the attack is not completely clear, but the pirates did not succeed in boarding the vessel and eventually fled.
The Liberian vessel MV Biscaglia was attacked on November 28, 2008. The security detachment aboard Biscaglia claimed to have used an LRAD device in an effort to repel attackers armed with assault rifles and rocket-propelled grenades. Following a one-sided shootout, the ship was seized and the unarmed security contractors abandoned ship leaving the ship and crew to the pirates. The incident caused the usefulness of LRADs to be called into question by Lloyd's List. In August 2013, Carl "Rocky" Mason, one of the three members of the security attachment aboard the Biscaglia during the incident, stated that an LRAD was aboard, but that he and the security attachment only had time to open the water cannons before gunfire and an RPG round forced them to abandon ship. No attempt was made to use the LRAD device during the incident.
London Olympics 2012
In February 2009, the Japanese whaling fleet operating in Antarctic waters near Australia installed LRADs on their vessels. The device was used against activists of the Sea Shepherd Conservation Society. The Japanese fleet later escalated the use of LRAD, deploying it against a Sea Shepherd helicopter carrying a camera crew. Sea Shepherd noted that they had an LRAD of their own, but as of early 2010, had not put it into use other than to play a recording of "Ride of the Valkyries" in the manner of attacking U.S. Army helicopters depicted in the 1979 film Apocalypse Now.
- Australia: Victoria Police, the Western Australian Police, the South Australia Police, the Queensland Police Service and the Australian Federal Police have confirmed they have purchased the devices.
- Azerbaijan: Azerbaijan police 
- Canada: Multiple police departments
- Hong Kong: Police Tactical Unit and Police Negotiation Cadre (PNC) of the Hong Kong Police Force
- India: Delhi Police
- Israel: Ministry of Defense
- Poland: Polish Police (Polish Police have it but for legal reasons it's not used)
- Singapore: Used by the Singapore Armed Forces
- Spain: Reported use by Catalan Police 
- Sweden: Swedish Navy 
- Turkey: Used by the Turkish Naval Forces
- United Kingdom: Ministry of Defence
- United States: Multiple police departments and US Army
- Vietnam: Being used on-board DN-2000-class ships of the Vietnam Coast Guard's fleet.
- Romania: Used first time on 7 June 2015 by Jandarmeria Romana
- Applications - LRAD Corporation website
- Corbett, Peter (2009). A Modern Plague of Pirates. p. 65. ISBN 0-9562107-0-8.
- LRAD Corporation website
- Beranek, Leo L. 1986. Acoustics, p.132, American Institute of Physics.
- Blackstock, David T. 2000. Fundamentals of Physical Acoustics, p.456, John Wiley and Sons.
- ABC News. Technology & Science. August 25, 2004. Amanda Onion. RNC to Feature Unusual Forms of Sound: Unusual Forms of Sound to Emanate From RNC
- Protesters Are Met by Tear Gas at G-20 Conference - NYTimes.com
- thetwos. YouTube.
- LRAD Corporation Announces Opening LRAD® Order from Israel's Ministry of Defense 
- Martin, Adam (25 October 2011). "Occupy Oakland's Tent City Is Gone". The Atlantic Wire. Retrieved 26 October 2011.
- "Occupy Wall Street: Police use military megaphone to amplify their point to protesters". New York Daily News. 18 November 2011. Retrieved 15 February 2015.
- "Exclusive: Delhi Police to use high-tech sound device to disperse unruly protesters". intoday.in.
- "MOBILNY LRAD-500X NA PŁYTĘ BOISKA". policja.waw.pl (in Polish). 11 August 2008.
- "Potężna broń służy jako zwykły głośnik. Policyjny system LRAD pod lupą prokuratury". rmf24.pl (in Polish). 9 January 2013.
- "As it Happens: NATO in Chicago". NBC Chicago.
- Bill Mich (8 October 2013). "Salisbury Police Utilizing New LRAD System". wboc.com.
- "DAY FIVE WRAPUP: McCulloch blasts Nixon for replacing St. Louis County Police control". St. Louis Post-Dispatch. August 14, 2014.
- (http://view.vzaar.com/2007295/video (2'45" - 3'10"))
- "Video: NYPD Uses Military-Grade Sonic Weapon on Eric Garner Protesters". Alternet.
- Tom O'Dare (19 March 2015). "Myrtle Beach police going high-tech for Bikefest". myhorrynews.com.
- NYPD LRAD warning message for protesters 4.29.15. YouTube. 29 April 2015.
- "Why The NYPD Is Cracking Down On Anti-Police Brutality Protests". mintpressnews.com.
- Justin Davis. "Police Deploy Tear Gas on Crowds Outside of Hot 97's Summer Jam - Complex". Complex.
- "Do Brna se kvůli demonstracím sjeli policisté ze Speciálních pořádkových jednotek z celé republiky". policejnidenik.cz (in Czech). June 26, 2015.
- Benjamin F. Powell (5 November 2015). "GDP: New Long Range Audio Technology Could Save Lives". wfmynews2.com.
- "Police order anti Trump protesters to disperse".
- Melissa Hawkes (26 February 2016). "The City Of Muskogee Considers Emergency Communication System". NewsOn6.com.
- Mark Hughes (27 February 2015). "Tech firm shows new long-range PA system". muskogeephoenix.com.
- Dalton Sweat (14 January 2016). "Wimberley flood siren". youtube.com.
- KVUE staff (9 June 2015). "12 dead, 2 children missing in Memorial weekend flooding". kvue.com.
- Jonathan Martinez (8 March 2016). "Rodeo officials prepare for looming storms". click2houston.com.
- Craig Hlavaty (8 March 2016). "RodeoHouston staff ready for whatever Houston's weather throws at them". chron.com.
- "Singapore Navy launches second littoral mission ship". NavalToday.com.
- "Việt Nam có thể ưu tiên mua sắm, trang bị vũ khí nào của Mỹ?". Anninh Thu do.
- "RPB 33 Offshore Patrol Boat, France". naval-technology.com.
- "I beat pirates with a hose and sonic cannon". BBC News. May 17, 2007. Retrieved May 11, 2010.
- "Login". timesonline.co.uk.
- David Osler, (2 December 2008). "Sonic solution may not be a sound investment", Lloyd's List. London: Informa. Retrieved 13 April 2011.
- "Pirate hunter: How a British ex-Marine and bodyguard to the stars escaped death fighting the most feared hijackers on the high seas - only to find they were run by a secret network of Somali spies in London". Mail Online.
- Sloan, Gene (January 17, 2011). "Cruise ship blasted pirates with sonic wave". USA Today. Retrieved July 17, 2011.
- "'Sonic weapon' deployed in London during Olympics". BBC News. 12 May 2012. Retrieved 11 May 2012.
- Darby, Andrew (February 6, 2009). "Whalers attack activists at sea". The Age. Melbourne.
- Sea Shepherd Conservation Society USA. "Video - Operation Waltzing Matilda". Operation Waltzing Matilda - Sea Shepherd Conservation Society.
- Sea Shepherd Battles Japanese Whalers in the Ross Sea - Sundance Channel, 7 February 2009
- "Street Fight on the High Seas". The New Yorker. 2010-01-12. Retrieved 2010-01-16.
- "Ride Of The Valkyries: Japanese Whalers Claim Sea Shepherd Harasses The Nisshin Maru With Classical Music". Underwatertimes.com. Tokyo. February 9, 2010. Retrieved January 1, 2011.
- Australian police authorities buying up sound weapons, The Law Report, ABC Radio, May 17, 2016
- This Pain-Inducing Acoustic Device Used to Control Crowds in Azerbaijan Might Be U.S.-Made, The Atlantic, March 14, 2013
- "La police de Montréal se dote de canons à son". La Presse.
- [=http://www.eldiario.es/politica/Centenares-personas-recorren-Madrid-Gamonal_0_219078935.html El Diario : News : Los mossos utilizan un cañón de sonido para dispersar a los manifestantes en Barcelona]
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